A steady flow air compressor compresses 50 lb/min from 14 psia and 80 degrees F to a discharge state at 45 psia and 300 degrees F. Heat departs from the air only via circulating water that enters the jacket at 75 degrees F and leaves at 95 degrees F, circulating at the rate of 15lb/min. Let the frictional losses external to the fluid be 10% of the fluid work. Determine (a) the size of the driving motor required and (b) the rate of the change of entropy of the air.
Ans. (a) 76.5 hp (b) .1195 Btu/degreesR-min.
I'm not sure how to deal with the information given to me concerning the water. I think I use the equation: W=m(cp)(T2-T1). I have never done a compressor problem before so I'm scrambling. I would appreciate as much help as you can give me.© BrainMass Inc. brainmass.com October 24, 2018, 5:18 pm ad1c9bdddf
This solution demonstrates how to find the size of the driving motor and the rate of change of entropy of the air using various equations. The answer is provided in an attached .bmp file.
Power required to drive the compressor
Please help with the following problem. Please provide step by step calculations.
Air enters a steady-flow compressor with a specific enthalpy of 293.4 kJ/kg and a velocity of 60m/s, and leaves with a specific enthalpy of 343 kJ/kg and a velocity of 120m/s. The mass flow rate of the air is 1kg/s, and the heat transfer rate from the air to the surroundings is 19kJ/s. Calculate the power required to drive the compressor. Assume the change of potential energy is negligible.View Full Posting Details